Perioperative risk and management in patients with pulmonary hypertension.

Pulmonary hypertension (PH) is a known risk factor for perioperative complications. Unlike in the case of cardiac surgery, PH is currently not listed as an independent risk factor for postoperative complications in guidelines for the management of noncardiac surgery. Despite the paucity of data, though, patients with PH are often counseled against having elective procedures because early and sudden postoperative deaths have been reported. Patients with PH are unable to accommodate alterations in right ventricular (RV) preload or afterload induced by fluid shifts, medications, or changes in the autonomic nervous system precipitated by hypoxia or hypercapnia. These factors become magnified in situations of added stress such as surgical intervention. Systemic hypotension and arrhythmias may precipitate RV ischemia, further worsening RV function. Patient and surgical characteristics and choice of anesthetic technique are crucial factors in perioperative management. The two main principles of perioperative management are the prevention of systemic hypotension (risk of RV ischemia) and the prevention of acute elevations in pulmonary arterial pressure (risk of RV failure). Close monitoring, optimization of systemic BP, pain control, oxygenation and ventilation, avoidance of exacerbating factors, and use of vasopressors and pulmonary vasodilators as necessary are essential elements of management. Understanding the pathophysiology, cause, and severity of PH in the individual perioperative patient allows accurate risk assessment, optimization of PH and RV function prior to surgery, and appropriate intraoperative and postoperative management.